Mental Health Bill: Categories of Mental Disorder (Hansard, 23 July 2002)

§ Lord Hunt of Kings Heath

The draft Mental Health Bill does not define particular categories of mental disorder. This means that no particular clinical diagnosis will have the effect of limiting the way the powers are used. The same conditions will be used to determine whether an individual falls within the scope of the legislation whatever their diagnosis.

The Government have not attempted to produce new definitions for the terms described, but would accept those in general usage and agreed clinical definitions. There is an internationally recognised classification system for personality disorder and these clinical definitions are accepted in relation to the term personality disorder where it is used in the consultation document attached to the draft Mental Health Act.

The World Health Organisation and the American Psychiatric Association have produced definitions of personality disorder. The International Classification of Mental and Behavioural Disorders (ICD-10) (World Health Organisation 1992), defines a personality disorder as: "a severe disturbance in the characterological condition and behavioural tendencies of the individual, usually involving several areas of the personality, and nearly always associated with considerable personal and social disruption". The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (American Psychiatric Association 1994) defines a personality disorder as: "an enduring pattern of inner experience and behaviour that deviates markedly from the expectations of the individual's culture".

The classification system does not distinguish between "personality disorder" and "severe personality disorder". The term "dangerous and severe personality disorder" is not a recognised clinical classification.

The term "severe personality disorder" is now in general use as a means of identifying, from within the millions of people with a degree of personality disorder in this country, the relatively small number whose condition is so serious as to require specialist interventions.

It is acknowledged that dangerous and severe personality disorder does not exist as a condition in its own right. The DSPD Programme has adopted the term DSPD as a working title and is currently developing—with clinicians and others—a supporting description that will be more meaningful to clinicians, lawyers and the general public. Any definition and description will be considered as part of the evaluation of the pilot projects.